The present invention relates to a flattened folding umbrella configuration, with improvement on the rib configuration, so that when the umbrella is folded, the whole body is naturally narrowed to become a flattened folding umbrella.
U.S. Pat. No. 5,615,697 provides a type of "POCKETABLE FOLDING UMBRELLA WITH FOLDABLE SANDWICHED RIBS", comprising mainly of: on top of the center rod (1) is fixed with a flat upper ferrule (3) which has a flat plate (31); said flat plate serves to define a long axis (X) on two extremities (E), and define a short axis (Y) between two sides (S); on the bottom of the flat plate (31) of said upper ferrule (3) on the two extremities (E) are each fitted with a terminal joining component (32) extending outward crosswise along the long axis (X), to join the inside of the inside main rib (21) of each terminal rib device (2); on the bottom of the flat plate (31) of said upper ferrule (3) near the sides (S) are each fitted with a side inclining wall (33); between each side inclining wall (33) and each terminal joining component (32) is joined to each side rib device (2a), with an upper tying thread (35) pulling through the inside of the inside main rib (21a) of each side rib device (2a), and through the inside of each terminal joining component (32); so that after the umbrella is folded, the outside joint (28a) of each side rib device (2a) can be located at the two sides of the terminal joining component (32); while the outside joint (22) of the terminal rib device (2) is located at the outward crosswise position of the terminal joining component (32), to avoid mutual overlapping of the outside joints of respective rib devices, to narrow it to become a flattened form.
However, the above prior art of flat folding umbrella, when it is folded, has the following occurrence that it could not achieve a properly flattened form. Referring to FIG. 1, the outside joint (28a) of each side rib device (2a) is joined by a bolt (284a) to the outside of the middle connecting rib (26a), while each terminal joining component (32) is joined by a bolt (321) to the inside of the inside main rib (21) of each terminal rib device (2); therefore, the joint of each bolt is especially enlarged; however, after said prior art is folded, the outside joint (28a) of each side rib device (2a) must be close to the upper ferrule (3) direction, but because said outside terminal and the upper ferrule (3) cannot be completely near, since there must be room to accommodate the fabric (5) after the umbrella is folded, therefore, the outside joint (28a) of each side rib device (2a), including its joining bolt (284a) is overlapped with the bolt (321) of each terminal joining component (32), resulting in especially enlarged width (W') of the overlapped portion; so it is impossible to achieve narrowing function and flattened form after it is folded.
Furthermore, referring to FIG. 2, in said prior art, each terminal rib device (2) is installed on the outside of the terminal joining component (32) protruding crosswise on the upper ferrule (3), while each side rib device (2a) is directly installed on the upper ferrule (3); suppose the crosswise length of the terminal joining component (32) is L1, and the length of each rib device is L, then, after the fold is opened, the horizontal extension length at the position of each rib device (2a) is L, and the horizontal extension length at the position of each terminal rib device (2) is L+L=L', therefore, in said prior art, after the umbrella is opened, the horizontal extension length of each terminal side device (2) and each side rib device (2a) is not consistent; and relatively, the fabric (5) tied to each rib device becomes non-equilateral polygons, thus resulting in uneven appearance of the umbrella; and the tensile strength of the fabric at each rib position is inconsistent, so the tightness on the fabric surface is uneven.